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Source for wiki ShortEquality version 1

author

cowan

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ipnr

127.11.51.1

name

ShortEquality

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R5RS and R7RS define `=` as accepting at least two arguments; it is an error to supply fewer.  However, that doesn't forbid Schemes from providing extension behavior.  This is an investigation of what Schemes in the suite do with `(=)` and `(= 1)`:

Returns `#t` for both `(=)` and `(= 1)`:  MIT, Gambit, Chicken, Guile, SCM, KSi, Sizzle

Signals an error for `(=)`, but returns `#t` for `(= 1)`:  Chez, Vicare, Ypsilon, !IronScheme, JScheme, STklos, XLisp, Elk, Llava, SXM

Signals an error for `(=)`, but returns `#f` for `(= 1)`:  !FemtoLisp

Signals an error in both cases:  Racket, Gauche, Bigloo, Scheme48/scsh, Kawa, SISC, Larceny, Mosh, NexJ, !SigScheme, Shoe, !TinyScheme, Scheme 9, RScheme, S7, BDC, Rep, Schemik, UMB, Dfsch, Inlab, Oaklisp, Sagittarius, Foment, Picrin, Owl Lisp, Chibi

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2015-05-31 23:51:54